Roll src/third_party/skia 99d792276740..4d657d5e894a (1 commits) (#8542)

https://skia.googlesource.com/skia.git/%2Blog/99d792276740..4d657d5e894a

git log 99d792276740293109edb22a26fea50490e7eeaf..4d657d5e894a7f89da68b5c41ae8e31128253e21 --date=short --no-merges --format=%ad %ae %s
2019-04-11 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader f0aa9d5ab738..3954a0bafb8a (42 commits)

The AutoRoll server is located here: https://autoroll.skia.org/r/skia-flutter-autoroll

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff (egdaniel@google.com), and stop
the roller if necessary.

DEPS

@@ -23,7 +23,7 @@ vars = {
   'fuchsia_git': 'https://fuchsia.googlesource.com',
   'github_git': 'https://github.com',
   'skia_git': 'https://skia.googlesource.com',
-  'skia_revision': '99d792276740293109edb22a26fea50490e7eeaf',
+  'skia_revision': '4d657d5e894a7f89da68b5c41ae8e31128253e21',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

ci/licenses_golden/licenses_skia

-Signature: 694d7fba29996869dade20431a948972
+Signature: 2c16cb44a8168a40836cfd5d7609b129
 
 UNUSED LICENSES: